Device for starting the balance wheel of timepieces



; March 23, 1954 H. BuEcHE-RossE 2,672,724

DEVICE FOR STARTING THE BALANCE WHEEL OF TIMEPIECES Filed Oct. 26, 1950 Patented Mar. 23, 1954 TING THE BALANCE DEVICE FOR STAR WHEEL OF TIMEPIECES Henri Bueche-Ross, Court,

J ura Bernois,

Switzerland Application October 26, 1950, Serial No. 192,310 Claims priority, application Switzerland October 28,

2 Claims.

be stopped limited period.

There are also, for example, so-called minute tacts for opening and closing termined period of time.

during a prede- In such devices to which the present invention is not limited, it

becomes necessary that after each winding operation a corresponding starting motion is to be set.

The aforesaid problem is solved in accordance with this invention by the fact that an element which is caused to turn during the winding operation is provided with an abutment which describes a circumferential path during such windis engaged by a fixed pin adapted to serve as a guide.

Such swing lever is then submitted to the action of a retraction spring which tends to reset the swing lever into predetermined position while said swing lever carries a fine and flexible stud element which, as soon as the swing lever is entrained by the abutment, is freed therefrom and swings to its starting position whereby for a moment the balance wheel is tangentially touched or contacted and an impulse is imparted thereto.

It is, therefore, one of the objects of the present invention to provide means simple in construction and operation for starting the driving mechanism of a time piece.

It is another object of the invention to provide means aifording the start of the balance wheel of a time piece during winding operation of the main spring.

It is still another object of the invention to provide means facilitating starting operation of the movement of the balance wheel in predetermined position during winding up manipulation.

With the above and other objects in view, the invention will be hereinafter more fully described and the combination and arrangement of parts will be shown in the accompanying drawing and whereby at the beginning of such acpointed out in the claims which form part of the specification.

The attached drawing shows schematically one of many possible embodiments of the invention.

Figs. 1 to 4 illustrate four different positions of the principal parts of the balance wheel mechanism.

Figs. 5 and 6 are detail views to which reference is made in the specification.

Referring now more particularly to the drawing there is disclosed a balance wheel I forming part of the movement of a time piece (not shown) which is wound up through a winding element and by means of axle 2 turned in the direction of the arrow A, as seen in Figs. 1 to 3. The rotatable member or winding element is designated by reference numeral 20.

In Fig. 1 an abutment element 3 is shown which is fixed to and adjacent the periphery of rotatable member 20 on axle 2 so that abutment 3 is rotated together with same. This abutment element is partially embraced and engaged by hook 4 of a swing lever 5. This swing lever is provided with a slot 6 which cooperates with a fixed'pin 1 adapted to guide and to limit shifting or displacement movements of swing lever 5.

This swing lever is also submitted to the action of a retraction spring 8 which is held with one of its ends by a screw 9 (on the frame of the time piece). The swing lever 5 further carries a fine and flexible stud element H! which projects from the swing lever in sideward direction to the balance wheel I, as seen in Fig. 5.

In the position, as seen in Fig. 1, the swing lever 5 assumes its normal rest or starting position into which spring, 8 always tends to retract the lever. As soon as one winds up the main spring of the movement, abutment element 3 is displaced in accordance with different strokes around the axle center 2 and in accordance with the direction of the arrow A.

During this movement the abutment element 3 engages and carries the swing lever 5 along by means of hook 4 until a limit position is reached, as illustrated in Fig 2, in which the pin 1 cooperates with the slot 6 which in turn prevents further displacement of the swing lever In this position the stud element In comes in contact with the balance wheel whereby, while the winding continues, hook 4 leaves and becomes disengaged from abutment element 3.

At this movement, as shown in Fig. 3, the swing lever 5 which has previously described a translatory movement and has started to osinto opposite or retracting position against the direction of the movement of the hands of a clock.

This swinging movement causes the end of flexible stud element It to slightly engage or touch the rim or profile of the balance wheel I which brings about flexing of the element and insures a good contact with the balance wheel (see Fig. 6).

From this position the retraction spring 8 becomes efiective and withdraws the swing lever suddenly to its starting position, as seen in Fig. 1. This lever is, therefore, shifted along slot 6 in the direction imparts an impulse to the balance wheel which it subsequently frees for oscillatory motion.

Therefore, one can easily visualize that it is impossible to wind up the clock or like movement without simultaneously imparting in one way or another an impulse to the balance wheel whereby starting of the movement is eliminated. In the event, that the rewinding operation necessitates several revolutions around the axle 2, it is clear that upon each rotation of abutment pin 3 past hook 4 the actuation just described is released and performed.

As soon as the member 20 carrying abutment element 3 is brought back during actuation the abutment 3 arrives again at its starting position and can thus pass several times hook 4 without disturbing the operation of the balance wheel.

Fig. 4 shows how the abutment element displaces and pushes back the suitably inclined end face l2 .of the head of hook 4 to thereby pass the swing lever (arrow B). The swing lever 5 may further oscillate around pin 1 and can, therefore, instantly take a position, as seen in Fig. 4, and subsequently return to the starting position depicted in 1. One can thus visualize that such operation is without any further influence on the balance wheel which stud element ID will not reach from position of Fig. 4 to position of Fig. 1. 7 Although the invention has been described with reference to a certain specific embodiment thereof, it is to be distinctly understood that various modifications and adaptations of the arrangements herein disclosed may be .made .as may readily occur to persons skilled .in the .art without constituting a departure from the spirit and scope of the invention as defined in the objects and in the appended claims.

Having thus described the invention. what is claimed as new and desired to be secured by Letters Patent, is:

1. The combination with .a timepiece mechanismincluding a balance wheel and a rotatable winding element, of an intermittently operated means for imparting an impulse to said balance of the arrow ll and element ll a hook engageable with wheel during each revolution oi said winding element, said means comprising a slidable and swingable lever provided with a camming surface, pin and slot means for mounting said lever for sliding movement between two limiting positions and for swinging movement during at least a portion of said sliding movement, resilient means operatively connected to said lever for biasing the latter into one of said limiting positions, a stud member carried by said lever and movable into bearing engagement with said balance wheel in response to the movement of said lever from said one limiting position into the other of said limiting postions, and an abutment operatively connected to said winding element and engaging said camming surface for displacing the latter into said other limiting position responsive to each revolution of said winding element, said camming surface being shaped to swing said lever while in said other limiting position in a direction to release said lever from engagement with said winding element through said abutment, whereby said lever is returned to said one limiting position under the action of said resilient means and causes said stud memher to impart an impulse to said balance wheel of said time-piece mechanism.

2. A device for starting the balance wheel of the movement of a time piece, comprising a rotatable member operatively connected to said movement, an abutment pin arranged adjacent the periphery of said member, a retracting spring, swing lever having at least three extremities, the first one of said extremities terminating in said abutment pin, the second one of said extremities being connected to said retracting spring, said swing lever being provided with an elongated slot positioned intermediate said first and second extremities, a stationary guide pin located in said slot for per.- mitting a pivotal and sliding connectionior swing lever to thereby engage said hook on said abutment pin and tensionsaid retracting spring upon rotation of said member, flexible stud means mounted on the third one of said extremities of said swing lever and engageable with said balance wheel for imparting movement'to the latter when said hook is disengaged ,fromsaid abutment pin and said swing lever is displaced by said retracting spring upon further rotation of said member.

HENRI BuEcHn-Rossn References Cited in the file of this patent UNITED STATES PATENTS Number Name p g 1,865,965 Ruiz July 5, .1932 1,943,079 Kienzle Jan. 9. 1934 2,318,615 Martin May 11, 1943 

